Department of Trauma-, Hand-, and Reconstructive Surgery, Westfälische Wilhelms-University Münster, Albert-Schweitzer-Campus 1, W1, Münster 48149, Germany.
BMC Musculoskelet Disord. 2013 Dec 21;14:360. doi: 10.1186/1471-2474-14-360.
Treating traumatic fractures in osteoporosis is challenging. Multiple clinical treatment options are found in literature. Augmentation techniques are promising to reduce treatment-related morbidity. In recent years, there have been an increasing number of reports about extended indication for augmentation techniques. However, biomechanical evaluations of these techniques are limited.
Nine thoracolumbar osteoporotic spinal samples (4 FSU) were harvested from postmortem donors and immediately frozen. Biomechanical testing was performed by a robotic-based spine tester. Standardized incomplete burst fractures were created by a combination of osteotomy-like weakening and high velocity compression using a hydraulic material testing apparatus. Biomechanical measurements were performed on specimens in the following conditions: 1) intact, 2) fractured, 3) bisegmental instrumented, 4) bisegmental instrumented with vertebroplasty (hybrid augmentation, HA) and 5) stand-alone vertebroplasty (VP). The range of motion (RoM), neutral zone (NZ), elastic zone (EZ) and stiffness parameters were determined. Statistical evaluation was performed using Wilcoxon signed-rank test for paired samples (p = 0.05).
Significant increases in RoM and in the NZ and EZ (p < 0.005) were observed after fracture production. The RoM was decreased significantly by applying the dorsal bisegmental instrumentation to the fractured specimens (p < 0.005). VP reduced fractured RoM in flexion but was still increased significantly (p < 0.05) above intact kinematic values. NZ stiffness (p < 0.05) and EZ stiffness (p < 0.01) was increased by VP but remained lower than prefracture values. The combination of short segment instrumentation and vertebroplasty (HA) showed no significant changes in RoM and stiffness in NZ in comparison to the instrumented group, except for significant increase of EZ stiffness in flexion (p < 0.05).
Stand-alone vertebroplasty (VP) showed some degree of support of the anterior column but was accompanied by persistent traumatic instability. Therefore, we would advocate against using VP as a stand-alone procedure in traumatic fractures. HA did not increase primary stability of short segment instrumentation. Some additional support of anterior column and changes of kinematic values of the EZ may lead one to suppose that additive augmentation may reduce the load of dorsal implants and possibly reduce the risk of implant failure.
治疗骨质疏松性创伤骨折具有挑战性。文献中发现了多种临床治疗选择。增强技术有望降低与治疗相关的发病率。近年来，关于扩展增强技术适应症的报道越来越多。然而，这些技术的生物力学评估是有限的。
从尸体供体中采集了 9 个胸腰椎骨质疏松性脊柱样本（4 个 FSU），并立即冷冻。生物力学测试由基于机器人的脊柱测试器进行。通过使用液压材料测试仪器进行骨切开样弱化和高速压缩的组合，创建了标准化的不完全爆裂骨折。对以下条件下的标本进行生物力学测量：1）完整，2）骨折，3）双节段器械化，4）双节段器械化伴椎体成形术（混合增强，HA）和 5）单独椎体成形术（VP）。确定运动范围（RoM）、中立区（NZ）、弹性区（EZ）和刚度参数。使用配对样本的 Wilcoxon 符号秩检验进行统计评估（p = 0.05）。
骨折后，RoM 以及 NZ 和 EZ 显著增加（p < 0.005）。在骨折标本上应用背侧双节段器械化后，RoM 显著降低（p < 0.005）。VP 减少了屈曲时骨折的 RoM，但仍显著高于完整运动学值（p < 0.05）。VP 增加了 NZ 刚度（p < 0.05）和 EZ 刚度（p < 0.01），但仍低于骨折前值。与器械化组相比，短节段器械化和椎体成形术（HA）的组合在 RoM 和 NZ 中的刚度没有显著变化，除了屈曲时 EZ 刚度的显著增加（p < 0.05）。
单独的椎体成形术（VP）在一定程度上支撑了前柱，但伴随着持续的创伤性不稳定。因此，我们不建议将 VP 作为创伤性骨折的独立治疗方法。HA 并没有增加短节段器械化的初始稳定性。前柱的一些额外支撑和 EZ 运动学值的变化可能会让人认为附加增强可能会减轻背侧植入物的负荷，并可能降低植入物失败的风险。
